1. Field of the Invention
The disclosure relates to a network apparatus.
2. Description of the Prior Art
For the improvement of physical layers, a data rate of a network connection has increased from 10 Mb/s to 100 Mb/s and 1000 Mb/s. In order to be downward compatible with previous data rates, IEEE (Institute of Electrical and Electronics Engineers) standard 802.3-2005 supports three data rates (10 Mb/s, 100 Mb/s and 1000 Mb/s). Before two Ethernet physical layers are linked, an auto-negotiation function is performed to confirm a highest data rate supported by these two Ethernet physical layers, and thus the two Ethernet physical layers establish a link at this highest data rate.
IEEE standard 802.3az EEE (Energy Efficiency Ethernet) is recently developed. An Ethernet physical layer supporting this standard needs to confirm the highest data rate of a far-end Ethernet physical layers and to confirm whether the far-end Ether physical layer supports this standard in the process of auto-negotiation. Being downward compatible with a previous version such as IEEE standard 802.3-2000 is what an Ethernet physical layer supporting IEEE standards 802.3-2005 and IEEE 802.3az (EEE) aims for.